Box



Nov. 6, 1945.

Original Filed Aug. 2l, 1941 Patented Nov. 6, 1945 UNITED psTATE BOX` Malcolm?. Junkin, Drexel-Hill, Pa.

original application August v21, 1941, serial No.

407,764. Divided and this application March 16,1942, Serial No. 434,819 i 4 claims. (el. 22e-49)' This invention relates to anv improvement in method and apparatus for producing stayed boxes and box produced thereby.

More particularly, this invention relates to the production of boxes of thetype produced from brous materiaLsuch, for example, as pasteboard, cardboard, bre board, `and the like,.and which heretofore have been providedwith ,corner stays formed from metal.

Thestayed box according to this invention is formed from brous material and `is characterized by the fact that it is provided with corner stays formed from plastic material and adhered at intervals to the fibrous material of the box, or through the body of the box to an inside corner stay of plastic material, by heatingand subjecting to pressure.

The method and apparatus according to this invention will be adapted for the application of heat and pressure at points ona plastic stay, positioned relative to thecorner of a bo'x formed from fibrous material, to at once force the plastic locally into the body of the box and causeits adherence to the bres of the body, orto force the plastic through the body of the box and eect its adherence to an inside stay of vplastic material.

Having now indicated in a general Way the nature of this invention, I will proceed to a detailed description of a preferred embodiment thereof with reference to the accompanying drawing, in

Which 2 pivoted at its other end tothe framel and conlnected to the cross head through a toggle link 8 Mounted on a bracket 9 secured tothe frame is a roll oi strip plastic material Ill, whichis led through a throat or guide II and fed into the die by means of the' usual type of feed pawl I2,

the plastic strip being provided.` with `spaced perforations for engagementofthe pawl.

Anywell known form of cut-off mechanism will be provided for cutting orf the stripin stay lengths.

lThe plastic strip IIl will be composed of any suitable thermoplastic material. Desirably the strip I will have a relatively low melting `point to the end that it may be rendered `plastic for adherence to a box under relatively low temperature and` pressure. The strip vli4 will haveany desired thickness and width within wide limits and may be of any desired color. While the strip I0 may be formed from various thermoplasticsgfor exi- Figure l is a side View of a machine for applying plastic corner stays to a box.

Figure 2 is a cross sectional view showing details of the machine shown in Figure 1.

Figure 3 is -a side view oi a detail of construction of the machine shown in Figures 1 and 2.

Figures 4, 5 and 6 are views, partly in section, showing modification in details of the machine shown in Figure 2 for adhering a plastic stay to the corner of a box.

Figure 7 is a plan view of a corner portion of a box blank of fibrous material, A

Figure Sis a sectional view of the corner of a box stayed with a plastic stay.

Referring more particularly to Figure 1, the machine illustrated comprises a frame I, from which is supported an anvil 2, above which is a die 3, supported from a cross head 4 engaging guides 5. The die 3 is adapted to be lowered and raised with respect to the anvil, as in the usual well known box staying machine, through the medium of the usual connecting rod 6 connected at one of its ends to a driven shaft, not shown, and connected at its other end to an end of a lever 1,

ample, it may be formed from cellulose acetate,`

or the like. l i t Referring now more particularlyto Figures 2 5,

the anvil 2 `will have in general the form `usual in well known box staying machine structuresfor support of the corner portion oi a fibre board box I3 to Which a stay I4 is to be applied.l The anvil will further' be provided with chamber I5 extending lengthwise adiacent its working faces forv the reception of a heating medium, as`,"for example, superheated steam, or heating means, as a suitable electric resistance type heater, in order that the working faces of the anvil may be heated to facilitate the adherence of the plastic stay.

The die 3 will be constructed in general in the form usual to box staying machines for cooperation with the anvil 2. The die will be provided with opposite grooves I6, I6 for the reception and support of the strip IIl of plastic material by the pawl I2 and will be formed so as to act to bend or form the strip I0 about the corner portion of the box I3. The die will further be provided with a series of hot points I1 extending from its opposite faces. The hot points Il, as shown in Figure 2, may be formed from any usual form of resistance material used in the formation of electrical heating units, and, secured to conducting bars I8 supported in recesses I9 in the sides of the die, extend through insulating sleeves 20 beyond the working faces of the die. The conducting bars I8 are connected in circuit with a source of electric current, the circuit being indicated at 2|. The hot points I1 will be arranged in spaced relation longitudinally of the opposite faces oi the die, as shown by Figures 2 and 3, and will extend beyond the faces suiciently to press or cut the plastic.

material of the strip I into the body of the fibrous material of the box I3 when the die is brought down'on the anvil, While, at the same time, heating the plastic material to render it adherent to the fibre.

As shown in Figure 2, the hot points maybe rounded at their ends to indent the plastic into the body ofthe box, as at 22, or, again, as shown in Figure 4', their ends may be hollowed out to present sharp edges to, in effect, cut the plastic into the box body with formation of .Spud-like projections 23. If desired, the ends of the ho points Il may be bevelled, as shown in Figure and the points positioned to forceV the edge portions of the plastic strip into the box body, as shown at 24, Figure 5. j y

moplastic material adhered to the nbre of the box body or to an inner stayr through the box body. It will be appreciated that it is not intended that this invention be limited in detail to the specific description herein of preferred embodiments, since it Will be apparent that various modications may be made Without departing from thel scope ofthe claims appended hereto.

v:'Ihisapplication is a division of application Serial No. 407,764, led August 21, 1941.

What I claim and desire to protect by Letters Patent is: 1. In combination a box body having adjacent Walls forming a corner, said body being formed The dies shown in Figures 4 and 5 are provided with chambers adjacent their working faces for the reception of a heating medium or heating means, to the end that the Working faces of the die, as well'as the hot points l1, Will be heated, thereby facilitating the formation of the strip l about the corner of the box.

Referring now to Figures 6-8, the box body I3 is provided adjacent its corners with perforations 26 and an inside stay I 0, of plastic material is applied in addition tothe outside stay provided by strip I0.' The hot points l1 carried by the die act to force the outer stay through the perforations 26 into adherent engagement with the inner stay Hl', Vthus securingr the stays to the box body, as shown at 21, Fig. 8.

It will now be appreciated that the apparatus and method in accordance With this invention, While comprising in general apparatus and procedure heretofore used in the application to boxes of metal stays, is essentially distinguished therefrom in the provision of hot points in connection With the die, and variously in heating the Working faces of the die and anvil to effect formation of a thermoplastic` stay about the corner of a boX and adherence of the stay at points to the bre of the body of the box, or to an inner stay through the body of the box, by heat and pressure applied through the medium of the hot points.

The product according to this invention, as will be appreciated, comprises a box of fibrous material provided at its corners with stays. of therfrom -Iibrous material, and a corner stay formed from a strip of thermoplastic material about a corner of the .body and adhered to bre of the adjacent Walls of the bodyrby the application of heat and pressure at separated points only on the strip.'

2. In combination a box body having adjacent walls forming a corner, said body being formed from fibrous material, and a corner stay formed from a strip of thermoplastic material about a corner of the body and secured thereto by adherence to fibre within adjacent walls of the body through the application of heat and pressure at points on the strip.

3. In combination a box body having adjacent Walls forming a corner, said body being formed -from brous material, and a corner stay formed from a strip of thermoplastic material about a corner of the body and secured thereto by adherence to fibre at the surface of adjacent Walls ofthe body through the application of heat and pressure over the surface of the strip and to fibrewithin adjacent walls of the body through the application of heat and pressure concentrated at points on the strip'.

' MALCOLM P. JUNKIN. 

